use crate::ast::node::named::Named;
use crate::ast::node::names::Identifier;
use crate::ast::node::use_statement::UseStatement;
use std::cell::RefCell;
use std::fmt::{Debug, Display, Formatter};
use std::ops::Deref;
use std::range::Range;
use std::rc::Rc;

#[derive(Clone, Debug)]
pub struct SourceDefinition {
    file_id: usize,
    range: Range<usize>,
}

impl SourceDefinition {
    pub fn from_identifier(identifier: &Identifier) -> Self {
        SourceDefinition {
            file_id: identifier.file_id(),
            range: identifier.range(),
        }
    }

    pub fn from_identifier_rc(identifier: Rc<RefCell<Identifier>>) -> Self {
        let borrowed = identifier.borrow();
        SourceDefinition {
            file_id: borrowed.file_id(),
            range: borrowed.range(),
        }
    }

    #[deprecated(note = "Use identifier instead.")]
    pub fn from_use_statement(use_statement: &UseStatement) -> Self {
        SourceDefinition {
            file_id: use_statement.file_id(),
            range: use_statement.range(),
        }
    }

    pub fn file_id(&self) -> usize {
        self.file_id
    }

    pub fn range(&self) -> Range<usize> {
        self.range.clone()
    }
}

pub trait SymbolInner {
    fn declared_name(&self) -> &str;
    fn definition(&self) -> Option<SourceDefinition>;
}

/* Symbol */

#[derive(Debug, Clone)]
pub enum Symbol {
    UseStatement(Rc<RefCell<UseStatementSymbol>>),
    Module(Rc<ModuleSymbol>),
    Type(Rc<TypeSymbol>),
    Function(Rc<RefCell<FunctionSymbol>>),
    Parameter(Rc<ParameterSymbol>),
    Variable(Rc<VariableSymbol>),
    ClassMember(Rc<ClassMemberSymbol>),
}

impl Symbol {
    pub fn definition(&self) -> Option<SourceDefinition> {
        match self {
            Symbol::UseStatement(s) => s.borrow().definition(),
            Symbol::Module(s) => s.definition(),
            Symbol::Type(s) => match s.deref() {
                TypeSymbol::Concrete(cts) => cts.definition(),
                TypeSymbol::Generic(gts) => gts.definition(),
            },
            Symbol::Function(s) => s.borrow().definition(),
            Symbol::Parameter(s) => s.definition(),
            Symbol::Variable(s) => s.definition(),
            Symbol::ClassMember(s) => s.definition(),
        }
    }

    pub fn unwrap_use_statement_symbol(&self) -> Rc<RefCell<UseStatementSymbol>> {
        match self {
            Symbol::UseStatement(s) => s.clone(),
            _ => panic!("unwrap_use_statement_symbol called on non-use statement symbol"),
        }
    }
}

/* Use-statement */

pub struct UseStatementSymbol {
    pub fqn: String,
    pub declared_name: String,
    definition: Option<SourceDefinition>,
    referenced_symbol: Option<Box<Symbol>>,
}

impl UseStatementSymbol {
    pub fn new(fqn: &str, declared_name: &str, identifier: Option<&Identifier>) -> Self {
        UseStatementSymbol {
            fqn: fqn.to_string(),
            declared_name: declared_name.to_string(),
            definition: identifier.map(SourceDefinition::from_identifier),
            referenced_symbol: None,
        }
    }

    pub fn set_referenced_symbol(&mut self, referenced_symbol: Symbol) {
        self.referenced_symbol = Some(Box::new(referenced_symbol));
    }

    pub fn referenced_symbol(&self) -> Option<Box<Symbol>> {
        self.referenced_symbol.clone()
    }
}

impl SymbolInner for UseStatementSymbol {
    fn declared_name(&self) -> &str {
        &self.declared_name
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for UseStatementSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("UseStatementSymbol")
            .field("fqn", &self.fqn)
            .field("declared_name", &self.declared_name)
            .field("referenced_symbol", &self.referenced_symbol)
            .finish()
    }
}

/* Module */

pub struct ModuleSymbol {
    fqn: String,
    declared_name: String,
    is_public: bool,
    definition: Option<SourceDefinition>,
}

impl ModuleSymbol {
    pub fn new(
        fqn: &str,
        declared_name: &str,
        is_public: bool,
        identifier: Option<&Identifier>,
    ) -> ModuleSymbol {
        ModuleSymbol {
            fqn: fqn.to_string(),
            declared_name: declared_name.to_string(),
            is_public,
            definition: identifier.map(SourceDefinition::from_identifier),
        }
    }
}

impl SymbolInner for ModuleSymbol {
    fn declared_name(&self) -> &str {
        self.declared_name.as_str()
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for ModuleSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("ModuleSymbol")
            .field("fqn", &self.fqn)
            .field("declared_name", &self.declared_name)
            .field("is_public", &self.is_public)
            .finish()
    }
}

/* TypeSymbol */

#[derive(Debug)]
pub enum TypeSymbol {
    Concrete(ConcreteTypeSymbol),
    Generic(GenericTypeSymbol),
}

impl TypeSymbol {
    pub fn declared_name(&self) -> &str {
        match self {
            TypeSymbol::Concrete(t) => t.declared_name(),
            TypeSymbol::Generic(t) => t.declared_name(),
        }
    }
}

pub struct ConcreteTypeSymbol {
    fqn: String,
    declared_name: String,
    is_public: bool,
    definition: Option<SourceDefinition>,
}

impl ConcreteTypeSymbol {
    pub fn new(
        fqn: &str,
        declared_name: &str,
        is_public: bool,
        identifier: Option<&Identifier>,
    ) -> Self {
        ConcreteTypeSymbol {
            fqn: fqn.to_string(),
            declared_name: declared_name.to_string(),
            is_public,
            definition: identifier.map(SourceDefinition::from_identifier),
        }
    }

    pub fn fqn(&self) -> &str {
        &self.fqn
    }

    pub fn is_public(&self) -> bool {
        self.is_public
    }
}

impl SymbolInner for ConcreteTypeSymbol {
    fn declared_name(&self) -> &str {
        &self.declared_name
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for ConcreteTypeSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("TypeSymbol")
            .field("fqn", &self.fqn)
            .field("declared_name", &self.declared_name)
            .field("is_public", &self.is_public)
            .finish()
    }
}

pub struct GenericTypeSymbol {
    declared_name: String,
    source_definition: SourceDefinition,
}

impl GenericTypeSymbol {
    pub fn new(declared_name: &str, source_definition: SourceDefinition) -> Self {
        GenericTypeSymbol {
            declared_name: declared_name.to_string(),
            source_definition,
        }
    }
}

impl SymbolInner for GenericTypeSymbol {
    fn declared_name(&self) -> &str {
        self.declared_name.as_str()
    }

    fn definition(&self) -> Option<SourceDefinition> {
        Some(self.source_definition.clone())
    }
}

impl Debug for GenericTypeSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("GenericTypeSymbol")
            .field("declared_name", &self.declared_name)
            .finish()
    }
}

/* Function */

pub struct FunctionSymbol {
    fqn: String,
    declared_name: String,
    is_public: bool,
    is_platform: bool,
    definition: Option<SourceDefinition>,
    parameters: Vec<Rc<ParameterSymbol>>,
    return_type: Option<Rc<ConcreteTypeSymbol>>,
}

impl FunctionSymbol {
    pub fn new(
        fqn: &str,
        declared_name: &str,
        is_public: bool,
        is_platform: bool,
        identifier: Option<&Identifier>,
    ) -> FunctionSymbol {
        FunctionSymbol {
            fqn: fqn.to_string(),
            declared_name: declared_name.to_string(),
            is_public,
            is_platform,
            definition: identifier.map(SourceDefinition::from_identifier),
            parameters: Vec::new(),
            return_type: None,
        }
    }

    pub fn with_parameters(self, parameters: Vec<ParameterSymbol>) -> Self {
        Self {
            fqn: self.fqn,
            declared_name: self.declared_name,
            is_public: self.is_public,
            is_platform: self.is_platform,
            definition: self.definition,
            parameters: parameters
                .into_iter()
                .map(|parameter| Rc::new(parameter))
                .collect(),
            return_type: self.return_type,
        }
    }

    pub fn with_return_type(self, return_type: ConcreteTypeSymbol) -> Self {
        Self {
            fqn: self.fqn,
            declared_name: self.declared_name,
            is_public: self.is_public,
            is_platform: self.is_platform,
            definition: self.definition,
            parameters: self.parameters,
            return_type: Some(Rc::new(return_type)),
        }
    }

    pub fn fqn(&self) -> &str {
        &self.fqn
    }

    pub fn set_parameters(&mut self, parameters: Vec<Rc<ParameterSymbol>>) {
        self.parameters = parameters;
    }

    pub fn set_return_type(&mut self, return_type: Rc<ConcreteTypeSymbol>) {
        self.return_type = Some(return_type);
    }
}

impl SymbolInner for FunctionSymbol {
    fn declared_name(&self) -> &str {
        self.declared_name.as_str()
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for FunctionSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("FunctionSymbol")
            .field("fqn", &self.fqn)
            .field("declared_name", &self.declared_name)
            .field("is_public", &self.is_public)
            .field("is_platform", &self.is_platform)
            .field("parameters", &self.parameters)
            .field("return_type", &self.return_type)
            .finish()
    }
}

/* Parameter */

pub struct ParameterSymbol {
    declared_name: String,
    definition: Option<SourceDefinition>,
}

impl ParameterSymbol {
    pub fn new(declared_name: &str, identifier: Option<&Identifier>) -> Self {
        ParameterSymbol {
            declared_name: declared_name.to_string(),
            definition: identifier.map(SourceDefinition::from_identifier),
        }
    }
}

impl SymbolInner for ParameterSymbol {
    fn declared_name(&self) -> &str {
        &self.declared_name
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for ParameterSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("ParameterSymbol")
            .field("declared_name", &self.declared_name)
            .finish()
    }
}

/* Variable */

pub struct VariableSymbol {
    declared_name: String,
    is_mutable: bool,
    definition: Option<SourceDefinition>,
}

impl VariableSymbol {
    pub fn new(declared_name: &str, is_mutable: bool, identifier: Option<&Identifier>) -> Self {
        VariableSymbol {
            declared_name: declared_name.to_string(),
            is_mutable,
            definition: identifier.map(SourceDefinition::from_identifier),
        }
    }
}

impl SymbolInner for VariableSymbol {
    fn declared_name(&self) -> &str {
        self.declared_name.as_str()
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for VariableSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("VariableSymbol")
            .field("declared_name", &self.declared_name)
            .field("is_mutable", &self.is_mutable)
            .finish()
    }
}

/* Class Member */

pub struct ClassMemberSymbol {
    declared_name: String,
    is_field: bool,
    definition: Option<SourceDefinition>,
}

impl ClassMemberSymbol {
    pub fn new(declared_name: &str, is_field: bool, definition: Option<SourceDefinition>) -> Self {
        ClassMemberSymbol {
            declared_name: declared_name.to_string(),
            is_field,
            definition,
        }
    }
}

impl SymbolInner for ClassMemberSymbol {
    fn declared_name(&self) -> &str {
        self.declared_name.as_str()
    }

    fn definition(&self) -> Option<SourceDefinition> {
        self.definition.clone()
    }
}

impl Debug for ClassMemberSymbol {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("ClassMemberSymbol")
            .field("declared_name", &self.declared_name)
            .finish()
    }
}